Fat in the cells are triglycerides. During exercise, triglycerides are metabolized while keeping their fat-free mass intact. These molecules are broken down through the process of oxidation, breaking them down glycerol and fatty acids. The liver, kidney, etc absorb the fatty acids to produce energy and heat. The usable portion of fat is converted to energy,
Curejoy Expert Dipti Mothay Explains:
Fat is one of the three main macro nutrients. Fats are a wide group of compounds whose basis is in long-chain organic acids, called fatty acids. Fats serve both as energy sources for the body, and as stores for energy in excess of what the body needs immediately.
Each gram of fat when burned or metabolized releases about 9 food calories. Fats are broken down in the healthy body to release their constituents, glycerol and fatty acids. Glycerol itself can be converted to glucose by the liver and so become a source of energy. Thus the mechanism the body uses to remove fat is biochemical and complex. Most functions of the human body work via a series of chemical processes.
A vast majority of doctors, dietitians, and personal trainers believe that when you burn fat during exercise, that fat is being used up as fuel for energy or heat. While some believe that by the law of conservation of mass, the only way your body can lose any amount of mass is for that amount of mass to pass out through the surface in the form of excretion, exhaling and sweating.
Breaking down Fat
During exercise the fat you burn is used as energy, the body empties the fat cell. Technically, the “fat” in the cells are triglycerides. When people attempt to lose weight, they are attempting to metabolize these triglycerides while keeping their fat-free mass intact. Triglycerides are comprised of three types of atoms: carbon, hydrogen and oxygen. Triglyceride molecules can be broken down only by unlocking these atoms, through a process known as oxidation.
Once removed, enzymes break down the triglycerides into two components, glycerol and fatty acids. The liver, kidneys and muscles absorb the glycerol and fatty acids to produce energy and heat. Waste products from the breakdown are excreted by the body through urine, expiration and sweat. The usable portion of fat is transferred to energy and the unusable portion leaves the body as waste.